Jaw clutch meshing device



Aug. 1958 J. c. VAlDEN 2,849,094

JAW CLUTCH MESHING DEVICE Filed June 28, 1955 INVENTOR. JOHN C'. VAIDE NJAW CLUTCH MESHIN G DEVICE John C. Yaiden, Packanack Lake, N. J.,assignor to Bend1x Aviation Corporation, Teterboro, N. J., a corporationof Delaware Application June 28, 1955, Serial No. 518,441 6 Claims. (Cl.192-67) This invention relates to engine starter meshing mechamsm. It isparticularly concerned with a novel jaw clutch meshing device.

The general object of the invention is to prevent customary clashing ofthe jaws of a starter with those of an engine during engagingoperations, as well as to prevent ratcheting of the jaws duringdisconnect operations.

This general object is accomplished by blocking means, associated withthe starter and interposed between the jaws of the starter and of anopposed engine. The arrangement of the blocking means is such as toallow engagement of the opposed jaws without clashing during startingoperations, and to block the jaws from ratchetmg with one another whilethe jaws are disconnected. The actions of the blocking means arecontrolled by the rotation of the starter relative to that of theengine.

The invention further lies in the particular construction of the device,and in the general organization of its various parts, as well as intheir cooperative association with one another to produce the resultsintended. thlThe foregoing and other objects and advantages of s aconsideration of the detailed description which follows, taken togetherwith the accompanying drawings wherein an embodiment of the invention isillustrated. It is to be expressly understood, however, that thedrawings are for purposes of illustration and description and are not tobe construed as defining the limits of the invention.

In the drawings:

Fig. 1 is a longitudinal section through starter-engine meshingmechanism, embodying the invention and showing the several elementsengaged to one another;

Fig. 2 is a left end View of the starter jaw together With theassociated blocking member superimposed thereon;

Fig. 3 is a left end View of the starter jaw with the blocking memberremoved;

Fig. 4 is a right end view of the blocking member; and

Fig. 5 is a view similar to Fig. 1 but showing the blocking member andengine jaw disengaged from one another.

Reference is now directed to the several drawings wherein there isdisclosed a starter jaw member 1 having a jaw head 2 at the end of astub shaft 3. The latter slidably engages by internal straight splines acomplementary splined end 4 of a driving screw member 5. The jaw memberis prevented from sliding free of the screw member by a bolt 6. Bolt 6is axially secured, as by threads and nut 7, at one end in a center wall8 of the starter jaw member. The shank of the bolt passes freely intothe hollow interior of the screw member and through a ring stop 9internally of the latter. A compression coil spring 10 about the boltacts upon the jaw member, forcing it leftward on the splined end of thescrew member until a headed end 11 of the bolt limits against the stop9. The screw member 5 is helically operable by conventional starterdrive mechanism,

invention will appear more fully hereinafter from.

2,849,094 Patented Aug. 26, 1958 not shown, whereby it is caused to beadvanced axially outward and rotated, carrying the starter jaw member 1With it to engage and drive an associated engine jaw 12.

The starter jaw head 2 has formed in its end face at the marginal edgethereof a ring of teeth 14 (Fig. 3) which are engageable with acomplementary ring of teeth 15 (Fig. 5) formed in an end wall 16 aboutthe marginal edge of the engine jaw; whereby, upon engagement of the jawmembers (Fig. 1) and rotation of the starter jaw, the associated engineis cranked.

When the engine starts and picks up speed, exceeding that of the starterjaw member, the latter is thrust out of engagement by the fasterrotating engine jaw. Until the starter jaw driving mechanism, not shown,comes to rest, there is a tendency of the starter jaw to return towardthe rotating engine jaw. Here, an interposed blocking ring member 17blocks re-engagement of the opposed jaws, and thereby avoids ratchetingof the jaws which would otherwise occur.

The right end 18 of this blocking ring member is receivable in a shallowrecess 19 formed in the left end of the starter jaw. The teeth 14 of thestarter jaw border this recess. About the peripheral surface of theblocking ring is a ring of saw teeth 20 of slight radial thickness,which are engageable with the inner radial portion of the starter jawteeth 14. When the teeth of the blocking ring are fully engaged withthose of the starter jaw, the right end face of the blocking ring is inthe shallow recess 19 and in close proximity to the recessed wall 21 ofthe latter. The radial expanse of the starter jaw teeth is relativelygreater than that of the blocking ring teeth as well as that of theengine jaw teeth. It is able to accommodate the teeth of both of thelatter elements. The outer marginal portion 22 (Fig. 2) of the starterjaw teeth, which is not engaged by the teeth of the blocking ring, isengageable with the opposed complementary teeth of the engine jaw (Fig.1).

When the blocking ring and starter jaw are engaged, as in Fig. 1, theleft face of the thickened blocking ring projects axially a shortdistance beyond the engaged teeth to the left, as at 23 in Fig. 1. Toenable the teeth of the engine jaw to be engaged by the outer marginalportion 22 of the starter jaw teeth, the right end of the engine jaw isskirted, and the teeth of the engine jaw are formed in the end wall 16of this skirted portion. This skirted end provides a shallow recess 24which is only deep enough to accommodate the left end 23 of the blockingring to the extent required to enable the teeth of the starter jaw tofully bottom in the teeth of the blocking ring and in those of theengine jaw.

It is to be noted, that engagement of the teeth of the engine jaw withthe related portion of the starter jaw is only possible when theblocking ring is fully bottomed in the recess 24 and when the teeth ofthe blocking ring are engaged with their complementary portion of thestarter jaw teeth. When the blocking ring member is not so engaged, theends of its teeth are caused to rest upon blunted ends of the starterjaw teeth (Fig. 5). When the blocking ring is in the latter position,the starter jaw is blocked from engaging the marginal portion of itsteeth with those of the engine jaw. This is due to the shallowness ofthe recess 24 in the opposed engine jaw in which the blocking ringbottoms.

The blocking ring member is normally held in its disengaged position(Fig. 5) and has this position when the starter jaw mechanism is at restor is disengaged from the engine jaw. To obtain and hold this normallydisengaged position of the blocking ring, a ribbon type torsion spring25 is provided. One end of the latter is anchored at 26 to the recessedwall 21 in the starter jaw; and the other end 27 is retained (Figs. 2,4-) in a radial slot 28 formed in the inner wall of the blocking ring. Acircumferentially disposed pocket 29 in the right end face of theblocking ring is provided to overlie the anchored end 26 of the spring,so as to avoid interference of the anchoring means with operatingactions of the blocking ring. A second similarly disposed pocket 31 inthe right end face of the blocking ring is intended to overlie .a heavystud 32 projecting axially from the recessed wall of the starter jaw.

The relation of the blocking ring member to. the starter jaw is suchthat, when the torsion spring is wound slightly, the starter jaw andblocking ring are drawn angularly into engagement with one another. Whenthe spring is relaxed, these members are cammed out of engagement bytherelated teeth. The spring is limited in the extent to which it may relaxby a shoulder 33 of the pocket 31 limiting against the stud 32 (Fig.whereby the disengaged teeth of the blocking ring are caused to come torest upon blunted ends of the teeth of. the opposed starter jaw, as inFig. 5.

In the operation of the described mechanism to effect engagement of theopposed jaw members, actuation of the helical drive screw 5, inconventional manner, causes the starter jaw member to axially advancetoward the opposed engine jaw. Whereupon, the projecting end 23, whichhas afriction face, of the blocking ring enters the engine jaw recess.and frictionally grips the recessed. wall 24 of the latter. As a resultof the latter action,. the torsion spring is caused to be wound byrotation of the starter jaw. Thiswinding action of the spring permitsthe starter to move axiallly into meshing engagement with the blockingring; and, as the latter occurs, the outer portion 22 of the starter jawteeth engage the teeth of the engine jaw. The engaged members thenrotate as a unit, and the engine starts up.

Now, after the engine starts and accelerates to a speed greater thanthat of the starter jaw, the latter is, thrust out of engagement fromthe engine jaw. In this latter action the torsion spring relaxes andslides the starter jaw out of engagement from the blocking ring.Whereupon, the blocking ring is carried to its normal disengagedposition upon the blunt ends of'the starter jaw teeth, as in Fig. 5.Until the starter jaw has come to rest,v it tends to return toward thehigh speed rotating. engine jaw. If allowed to do so, clashing of theopposed teeth and possible damage would occur. The blocking ring,however, in its disengaged position, blocks against such clashing ofteeth.

While an embodiment of the invention has been illustrated and describedindetail, it is tobe expressly understood that the invention is notlimited thereto. Various changes can be made in the design andarrangement of the parts without departing from the spirit and scope ofthe invention, as the same will now be understood by those skilled inthe art; and it is my intent to claim the invention not only as shownand described, but. also in all such forms and modifications thereof asmay be reasonably construed to be within the spirit of the. inventionand the scope of the appended claims.

What is claimed is:

1. In engine starter jaw clutch meshing. mechanism of the characterdescribed, a starter driving jaw having. a.

ringof radially bro-ad saw teeth in an end face, an op.- posed.thickened ring having peripheral saw teeth engageable with the innerradial portion of the starter jaw teeth;

and torsion spring means. anchoring the thickenedring to the starter jawadapted, when wound in a particular direction, to permit the opposedmembers to move into toothed engagement with one another, and whenrelaxed, to assist to axially slide the ring out of toothed engagementfrom the opposed starter jaw.

2. 111 engine starter mechanism of the character described, a starterdriving jaw having a ring of radially broadsaw teeth in an end facethereof; an opposed thickened ring having peripheral saw teethengageable with the inner radial portion of the starter jaw teeth;ribbon type torsion spring means anchoring the thickened ring in opposedrelation to the starter jaw and adapted, when wound in a particulardirection, to permit the opposed members to move into toothed engagementwith one another, and when relaxed, to assist to axially slide thethickened ring out of toothed engagement from the starter jaw; and meansfor limiting the relaxed position of the torsion spring at a point wherethe ends of the teeth of the thickened ring abut the ends of the teethof the starter 3. In engine starter mechanism of the characterdescribed, a starter driving jaw having a ring of radially broad sawteeth in an end fact thereof; an opposed thickened ring havingperipheral saw teeth of small radial thickness engageable with the innerradial portion ofthe starter jaw teeth; a torsion spring anchoring thethickened ring in opposed relation to the starter jaw and adapted, whenwound in a particular direction, to permit the op.- posed members tomove into toothed engagement with one another, and when relaxed, toassist to axially slide the thickenedring out of such engagement; a studin a recess of the starter jaw; and a shoulder formed ina face of theopposed thickened ring cooperable with the. stud, upon relaxing of thetorsion spring, to limit the relaxed position of the torsion spring at apoint where the ends of the teeth of the thickened ring abut. the endsof the teeth of the starter jaw.

-4. In engine starter mechanism of the character described, a starterdriving jaw having in an end face a ring of radially broad blunt endedsaw teeth, an opposed thickened ring having peripheral saw teeth ofsmall radial thickness engageable with the inner radial portion of the.

starter jaw teeth; a torsion spring anchoring the thickenedring inopposed relation to the starter jaw and adapted, when wound in aparticular direction, to permit the opposed members to move into toothedengagement with one another, and when relaxed, to axially slide the.thick ened ring out of such engagement; a stud in a, recess of thestarter jaw engageable with a shoulder in the end face of the opposedthickened ring to limit the position ofthe latter, upon relaxing of thetorsion spring, to a point where the teeth of the thickened ring abutthe. bluntends of the teeth of the starter jaw.

5. In engine starter mechanism of the character, described: an axiallymovable and rotatable starter driving jaw having a ring of radiallybroad saw teeth in an end face thereof; an opposed engine jaw having inan end face thereof a ring of radially extending but relatively narrowersaw teeth engageable with the outer radial portion of the engine jawteeth; a thickened ring partly receivable axially in a recess of theengine jaw and having an end face adapted to frictionally engage anopposed wall of the recess; the ring having peripheral saw teeth aroundit of small radial thickness and engageable in the opposed inner radialportion of the starter jaw teeth; torsion spring means anchoring thethickened ring to the starter jaw; the torsion spring means having anormal position wherein the teeth of the thickened ring are axially heldout of engagement from the teeth of the starter jaw and the ends thereofabut the ends of the teeth of the latter, and having a wound positionwherein the teeth of the starter jaw are axially drawn into engagementwith those of the thickened ring and the teeth of the engine jaw; thethickened ring in normal position serving to space the starter jaw outof engagement from the engine jaw; and means for driving the starter jawaxially to move the end face of the ring into. frictional engagementwith the recessed wall of the engine jaw and for rotating the starterjaw, whereby the torsion spring is wound to draw the starter jaw intoengagement with the teeth of the thickened ring and those of the engine6. In engine starter mechanism of the character de scribed: an axiallymovable and rotatable starter driving jaw having a ring of radiallybroad saw teeth in an end face thereof; an opposed engine jaw having inan end face thereof a ring of radially extending but relatively narrowersaw teeth engageable with the outer radial portion of the engine jawteeth; a thickened ring partly receivable axially in a recess of theengine jaw and having an end face adapted to frictionally engage anopposed wall of the recess; the ring having peripheral saw teeth aroundit of small radial thickness and engageable in the opposed inner radialportion of the starter jaw teeth; torsion spring means anchoring thethickened ring to the starter jaw; said torsion spring means normallypositioning the teeth of the thickened ring axially out of engagementwith the teeth of the starter jaw and the ends thereof in abutment tothe ends of the teeth of the latter;

References Cited in the file of this patent UNITED STATES PATENTS2,574,004 Zingsheirn Nov. 6, 1951 2,667,252 Meyer Jan. 26, 1954 FOREIGNPATENTS 418,328 Great Britain Oct. 23, 1934 1,099,090 France Mar. 16,1955

